N3
ついに
Finally, At last
ついにドラゴンズが勝った！
The Dragons have finally won!
Explanation
「ついに」 means 'finally'. After a long time, much effort or many twists, the long-awaited result arrives: 「ついに夢が叶った」 (My dream finally came true). It can also be used for a bad ending, where things built up until this point, often with 「〜てしまった」: 「ついに倒産してしまった」 (It finally went bankrupt).
Mixed up with
「やっと」: after hard effort, it works out at last, with a sense of relief (I made it in time).
「ついに」: a big outcome after a long time, good or bad, with some weight.
「とうとう」: a bad trend kept going and a regrettable result came in the end (とうとう壊れてしまった).
「いよいよ」: an important moment is finally close (いよいよ明日出発だ).